Diodes Incorporated DDTC143EUA-7-F

Overview

DDTC143EUA-7-F from Diodes Incorporated is an NPN pre-biased small-signal transistor in SOT323 package with integrated bias resistors R1 = R2 = 4.7 kΩ, V_CEO = 50 V, I_C(MAX) = 100 mA, V_CE(SAT) ≤ 0.3 V at I_C/I_B = 10, and DC current gain (h_FE) ≥ 20 at I_C = 20 mA - used for digital switching in automotive body control modules.

For engineers reviewing the DDTC143EUA-7-F datasheet, DDTC143EUA-7-F pinout, DDTC143EUA-7-F application, or DDTC143EUA-7-F equivalent, key selection criteria include input voltage thresholds (V_IN(OFF) ≤ 1.1 V, V_IN(ON) ≥ 1.9 V), guaranteed saturation performance under 20 mA load, AEC-Q101 qualification, and SOT323 thermal resistance (R_θJA = 625 °C/W).

Technical Context

This device integrates two matched 4.7 kΩ bias resistors (R1 = R2) to configure a single-NPN inverter with fixed base biasing - eliminating external resistor placement while maintaining predictable turn-on/turn-off thresholds across temperature. Its epitaxial planar construction ensures stable h_FE and low V_CE(SAT) over -55°C to +150°C.

Designed for direct logic-level interfacing, it accepts TTL- or CMOS-compatible input voltages (V_IN(OFF) ≤ 1.1 V, V_IN(ON) ≥ 1.9 V at V_CC = 5 V) and delivers clean 100 mA sink capability with <0.3 V saturation, enabling reliable driving of LEDs, relays, and MOSFET gates without additional level-shifting circuitry.

Key Specifications

Pinout & Package

Package: SOT323 - surface-mount plastic case, 0.008 g weight, UL 94V-0 rated, moisture sensitivity level 1, matte tin-plated leads.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN pre-biased transistor applications.

Compared with DDTC123EUA-7-F and DDTC114EUA-7-F, DDTC143EUA-7-F strikes a balance: its 4.7 kΩ bias offers moderate input current (1.8 mA @ 5 V), robust 1.9 V turn-on threshold for mixed-voltage systems, and consistent 100 mA output capability - making it ideal for general-purpose automotive and industrial digital switching where reliability and compatibility outweigh extreme low-power or noise-immunity needs.

Availability

DDTC143EUA-7-F is available at Aetrix Electronics and suitable for automotive lighting control, industrial PLC output stages, and USB-C power path management requiring stable component supply and AEC-Q101 compliance.

Supply support for DDTC143EUA-7-F includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability components for automotive, industrial, and consumer markets.

This part belongs to the DDTC R1=R2 series of pre-biased transistors - designed specifically to simplify digital switching designs in space- and cost-constrained applications while meeting automotive qualification standards.

FAQ

What is the maximum continuous collector current for DDTC143EUA-7-F?

The absolute maximum collector current is 100 mA, verified per the DS30321 datasheet Absolute Maximum Ratings table. Electrical Characteristics confirm sustained 20 mA operation with guaranteed h_FE ≥ 20 and V_CE(SAT) ≤ 0.3 V under standard test conditions (V_CC = 5 V, I_C/I_B = 10). Derating applies above 25°C ambient per Fig. 1.

Is DDTC143EUA-7-F suitable for 3.3 V microcontroller interfacing?

Yes - its V_IN(ON) (typ. 1.9 V, max 3 V) and V_IN(OFF) (min. 0.5 V, typ. 1.1 V) ensure reliable switching with 3.3 V logic outputs. At V_IN = 3.3 V, input current is ~1.8 mA, well within GPIO sourcing limits of most modern MCUs without requiring external buffering.

Does this device require external bias resistors?

No - DDTC143EUA-7-F integrates matched 4.7 kΩ resistors (R1 = R2) internally, forming a complete single-transistor inverter stage. No external bias components are needed, reducing PCB area, assembly steps, and BOM complexity versus discrete transistor + resistor solutions.

What is the thermal resistance of DDTC143EUA-7-F on a standard FR-4 board?

R_θJA is 625 °C/W when mounted on an FR-4 PCB with Diodes Incorporated's minimum recommended pad layout (per Note 6 in DS30321). This value assumes no copper pour or thermal vias; adding 1-in² copper area reduces R_θJA to ~200 °C/W, enabling higher continuous current in thermally demanding applications.